Re: dynamic-hz

From: linux-os
Date: Wed Dec 15 2004 - 15:02:37 EST

On Wed, 15 Dec 2004, Alan Cox wrote:

On Maw, 2004-12-14 at 00:16, Eric St-Laurent wrote:

On a related subject, a few months ago you posted a patch which added a
nice add_timeout()/timeout_pending() API and converted many (if not
most) drivers to use it.

If I remember correctly it did not generate much comments and the work
was not pushed into mainline.

I think it's a nice cleanup, IMHO the time_(before|after)(jiffies, ...)
construct is horrible.

Any chance to resurrect this work ?

I plan to ressurect it when I have a little time but with some small
additions from the original work. Several people said "it should be mS
not HZ" and someone at OLS proposed that the API also includes an
accuracy guide so that systems using programmed wakeups can aggregate
timers when accuracy doesn't matter.

I sure hope it isn't mS. Transconductance or its reciprocal doesn't
work very well for timing unless you supply the capacitor ;^)

FYI, mS means milli-Siemens. Seconds is lower-case --always.

Dick Johnson
Penguin : Linux version 2.6.9 on an i686 machine (5537.79 BogoMips).
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